7. Chevy Chase - Community
No recent TV relationship has been as tumultuous (and publicly petty) as that between Community showrunner Dan Harmon and Chevy Chase. During Chase's four seasons on the cult show, he and Harmon were constantly at odds about the way the character of Pierce Hawthorne should be portrayed. For the most part, this made him hate being on the show.
According to Harmon and some of the other cast members, when Chase didn't "get his way" he would frequently succumb to his more childish instincts, stepping over his co-stars' dialogue and seemingly ruining takes on purpose. Joel McHale, the show's lead, once told Howard Stern that Chase simply "didn't want to be there" and that whenever he tried to get his co-star back on track, Chase would try to physically fight him.
That type of petulance is exactly what made his character, Pierce, so irritating to watch. It's also what made him an occasionally brilliant presence on a show that routinely went too far up its own butt. In a weird way, Pierce's aggressive bewilderment toward the other characters -- who were always one meta joke away from complete overload -- actually kept the show grounded.
And much of that came from Chase's real-life disinterest in the self-referential humor Harmon was so fond of. Chase voicing his bemusement through Pierce is what made the show relatable for much of the audience.